The ability to easily remotely manipulate instruments and tools is of interest in a wide variety of industries and applications, in particular where it is desired to control movements of instruments or tools in spaces difficult to access by hand, or areas that might otherwise present a risk or danger. These can include situations where the targeted site for the application of a tool or instrument is difficult to access during surgical procedures, or the manufacture or repair of machinery, or even during commercial and household uses, where manual access to a targeted site is restricted or otherwise. Other situations can include, e.g., industrial applications where the work environment is dangerous to the user, for example, workspaces exposed to dangerous chemicals. Still other situations can include, e.g., law enforcement or military applications where the user may be at risk, such as deployment of a tool or instrument into a dangerous or hostile location.
Using surgical procedures as an illustrative example, procedures such as endoscopy and laparoscopy typically employ instruments that are steered within or towards a target organ or tissue from a position outside the body. Examples of endoscopic procedures include sigmoidoscopy, colonoscopy, esophagogastroduodenoscopy, and bronchoscopy. Traditionally, the insertion tube of an endoscope is advanced by pushing it forward, and retracted by pulling it back. The tip of the tube may be directed by twisting and general up/down and left/right movements. Oftentimes, this limited range of motion makes it difficult to negotiate acute angles (e.g., in the rectosigmoid colon), creating patient discomfort and increasing the risk of trauma to surrounding tissues.
Laparoscopy involves the placement of trocar ports according to anatomical landmarks. The number of ports usually varies with the intended procedure and number of instruments required to obtain satisfactory tissue mobilization and exposure of the operative field. Although there are many benefits of laparoscopic surgery, e.g., less postoperative pain, early mobilization, and decreased adhesion formation, it is often difficult to achieve optimal retraction of organs and maneuverability of conventional instruments through laparoscopic ports. In some cases, these deficiencies may lead to increased operative time or imprecise placement of components such as staples and sutures.
Steerable catheters are also well known for both diagnostic and therapeutic applications. Similar to endoscopes, such catheters include tips that can be directed in generally limited ranges of motion to navigate a patient's vasculature.
There have been many attempts to design endoscopes and catheters with improved steerability. For example, U.S. Pat. No. 3,557,780 to Sato; U.S. Pat. No. 5,271,381 to Ailinger et al.; U.S. Pat. No. 5,916,146 to Alotta et al.; and U.S. Pat. No. 6,270,453 to Sakai describe endoscopic instruments with one or more flexible portions that may be bent by actuation of a single set of wires. The wires are actuated from the proximal end of the instrument by rotating pinions (Sato), manipulating knobs (Ailinger et al.), a steerable arm (Alotta et al.), or by a pulley mechanism (Sato).
U.S. Pat. No. 5,916,147 to Boury et al. discloses a steerable catheter having four wires that run within the catheter wall. Each wire terminates at a different part of the catheter. The proximal end of the wires extend loosely from the catheter so that the physician may pull them. The physician is able to shape and thereby steer the catheter by selectively placing the wires under tension.
Although each of the devices described above are remotely steerable, their range of motion is generally limited, at least in part because typically only a single cable set is employed in connecting links or segments of the steerable elements. As such, independent movement at each link or segment is not possible. Rather, the distal links or segments bend together as a unit or units. The steering mechanisms may also be laborious to use, such as in the catheter of Boury et al. where each wire must be separately pulled to shape the catheter. Further, in the case of e.g., endoscopes and steerable catheters that use knob and pulley mechanisms, it requires a significant amount of training to become proficient in maneuvering the device through a patient's anatomy.
Consequently, a device with enhanced remote maneuverability to controllably navigate complex anatomy may allow more efficient and precise advancement and deployment of surgical and diagnostic instruments and tools, as well as help decrease trauma to surrounding tissues, minimize patient discomfort, and decrease operative time and perhaps even patient morbidity during various surgical procedures. It would also be advantageous for such a device to provide a more intuitive and facile user interface to achieve such enhanced maneuverability.
A user interface that accurately translates finger movement of the human hand to a surgical instrument or tool is one way of achieving remote enhanced maneuverability. Although many attempts have been made to implement such a device, such as described in U.S. Pat. No. 5,441,494 to Ortiz; U.S. Pat. No. 5,807,376 to Viola et al.; and U.S. Pat. No. 5,813,813 to Daum et al., there still exists a need for a device with improved control and range of motion.
Thus, a device that not only provides a hand user interface, but an actuation mechanism that allows for close simulation of human hand movements to enhance remote maneuverability is highly desirable.